librtas: Release lock in error path
librtas: Release lock in error path

Release RMO buffer lock in error path. Otherwise we will continue to hold
the lock and subsequent RMO buffer allocation request fails.

Reported-by: Bharata B Rao <37852461ec08f94420c663824224090aed552843@linux.vnet.ibm.com>
Signed-off-by: Vasant Hegde <a6d753843573f7bfed5075c1e875b0be8007a0ab@linux.vnet.ibm.com>

nfont/librtas,nfont/librtas